The series is written by Jones, and focuses on Ruby, a woman living a humdrum existence who one day gets a text inviting her to fulfill a youthful pact, promising true love and self-reinvention, by stepping out of her life to take a journey with her oldest flame. Waller-Bridge will also star as a recurring character.

Gleeson will play Billy Johnson, a successful life guru from a wealthy Irish family. Born with the gift of gab, he deftly combines a boatload of charisma with a boundless need for approval.

Run will be the Irish actor's first major TV role. Gleeson, 35, is most well known for his role as Bill Weasley in the Harry Potter franchise and General Hux in Star Wars: The Force Awakens and Star Wars: The Last Jedi, with other credits including Ex Machina, Brooklyn, The Revenant and Peter Rabbit.

Gleeson’s latest projects are The Little Stranger, directed by Lenny Abrahamson, and Andrea Berloff’s The Kitchen, starring alongside Melissa McCarthy, Tiffany Haddish and Elisabeth Moss. Phoebe Waller-Bridge is currently shooting the second season of Fleabag, to air on BBC in 2019, and Killing Eve is airing on BBC3 on Sundays.